الفهرس 
Specific Energy EquationOnly 14 pages are availabe for public view
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Abstract
An open channel transition may be defined as a change either in the direction,slope or cross section of channel, which produces a change in flow conditions(non-uniform). Most transitions of engineering interest are comparatively short structures, although they may affect the flow for a great distance upstream or downstream.The transitions in circular open channel are considered as compound transition. The steady subcritical flow through circular open channels with increase in bed elevation by a slope (3 horizontal to 1 vertical) for formatting a flat base is examined. This transition is considered as a problem of open channel compound transitions (horizontal and vertical transitions).Considering a smooth and gradual transition zone for the subcritical approaching flow regime, the equations of energy, discharge, continuity and Froude number are used to solve this problem. The existing methods of solving these equations are: Trial-and-error solution, Graphical solution and Design tables prepared from the specific energy equation expressed in dimensionless form. Mathematical and experimental studied are used to achieve this transition.Using the energy, discharge, continuity and Froude number equations to find the critical rise in bed and the corresponding critical water depth were determined analytically and graphically. Also, the effects of the rise in bed,the discharge and upstream water depth on the flow characteristics are obtained using the experimental results.The rise in bed elevations with the formation of a flat base in circular open channel can be considered as a simple means of measuring flow discharge.The experimental studies are made to study the flow characteristics at the transition (water depth and Froude number at the transition). Also, it used to evaluate using the transition as a discharge measurement device in partially filled circular channel. The results of the mathematical equations compared with the experimental one.